Galileo Galilei was born onFeb 15,1564 in Pisa. Vincenzo Galilei and Guilia Ammannatiwere his parents. His family returned to florence, his father's hometown, in 1572 while Galileo himself stayed in Pisa and lived for two years with Muzio Tedaldi who was related to Galileo's mother. Two years later he left pisa to join his parents. Once he was old enough, his parents sent him to the Camaldolese Monastery at Vallombrosa. Vincenzo had Galileo come back because he wanted him to become a doctor. Galileo wasn't interested in medical school though, and never really took it seriously. He later attended coarses on mathamatics and natural philosiphy. In 1582-83 Ostilio Ricci gave classes on Euclid's Elements which Galileo attended. In 1585 he officially gave up his medical coarses. In 1585-86 Galileo fist started teaching mathamatics. In 1586 he started to teach at Vallombrosa and wrote the book The little balance, his first scienific book . described Archimedes' method of finding the specific gravities. Also in 1588 Galileo lectured on the dimensions and location of hell in Dante's Inferno at the Academy in Florence. Fantoni left the chair of mathematics at the University of Pisa in 1589 and Galileo filled his post. Galileo held thepost for three years in which he wrote the book De Motu a series of essays on the theory of motion which he never published. In 1591 Vincenzo Galilei, Galileo's father, died leaving galileo, the eldest son, to take care of his familly, but he was not well paid, so he took the job of professor of mathematics at the University of Padua in 1592 at a salary of three times what he had received at Pisa. He spent eighteen years at the university, years which he later described as the happiest of his life. He mainly taught Euslid's geometry and standard (geocentric) astronomy. However, Galileo argued against Aristotle's veiw of astronomy and natural philosophy in three public lectures he gave in connection with the appearance of a New Star (now known as 'Kepler's supernova') in 1604. Gallileo proved that the New Star couldnot be cose to earth. At Padua, Galileo began a long term relationship with Maria Gamba. In 1600 their first child Virginia was born, followed by a second daughter Livia in the following year. In 1606 their son Vincenzo was born.
In 1609, Galileo recieved this letter telling about a new Dutch spyglass:
About ten months ago a report reached my ears that a certain Fleming had constructed a spyglass by means of which visible objects, though very distant from the eye of the observer, were distinctly seen as if nearby. Of this truly remarkable effect several experiences were related, to which some persons believed while other denied them. A few days later the report was confirmed by a letter I received from a Frenchman in Paris, Jacques Badovere, which caused me to apply myself wholeheartedly to investigate means by which I might arrive at the invention of a similar instrument. This I did soon afterwards, my basis being the doctrine of refraction.
From these reports, and using his own technical skills, Galileo began to make telescopes that were much better than the Dutch one. His first telescope was able to magnify up to 4 times. His discoveries with his telescope were recorded in a book, Starry Messenger published in 1610. Galileo claimed to have seen mountains on the Moon and discovered the milky way was made up of stars. Galileo fist veiwed Saturn with his telescope on 25 July 1610 and it appeared as three bodies (his telescope was not good enough to show the rings but made them appear as blobs on both sides of the planet). Also in 1610 he discovered that, when seen in the telescope, the planet Venus showed phases like those of the Moon, and therefore must orbit the Sun not the Earth. Galileo became the chief of mathmaticians at the University of Pisa. He became a member of the Accademia dei Lincei. He studied the 4 moons of Jupiter. In his telescope, he looked at Saturn and it looked like it had three bodies on it. He discovered that Venus had phases like the moon does. He observed sunspots and recorded them in the book that he wrote. Galileo then became to study some comets. As you may remember, Gallileo was a supporter of Copernicus, and believed that the earth rotated around the sun. In 1616, he wrote this letter that proysted the followers of Aristotle, who believed the oposite:
I hold that the Sun is located at the centre of the revolutions of the heavenly orbs and does not change place, and that the Earth rotates on itself and moves around it. Moreover ... I confirm this view not only by refuting Ptolemy's and Aristotle's arguments, but also by producing many for the other side, especially some pertaining to physical effects whose causes perhaps cannot be determined in any other way, and other astronomical discoveries; these discoveries clearly confute the Ptolemaic system, and they agree admirably with this other position and confirm it.
The cardinals of the Inquisition met on 24 February 1616 to present evidence and decide if the bible says Copernicus's theory was wrong. Galileo's accusation at the trial which followed was that he had breached the conditions laid down by the Inquisition in 1616. After the trial, Galileo was no longer allowed to study the Copernican theory. Galileo was found guilty and he was condemned to lifelong imprisonment, although it was only house arrest. He was able to live first with the Archbishop of Siena, then later to return to his home in Arcetri, near Florence, but had to spend the rest of his life watched over by officers from the Inquisition. In 1634 he was heartbrocken to find out his daughter, virginia, had died. She had been a great help to her father in his sickness and Galileo was shattered and could not work for many months. When he did get back to work, he wrote Discourses and mathematical demonstrations, concerning the two new sciences. When he finished his work on Discurages, it was smugled out of Italy to London, where it was published. In the Discourses he developed his ideas of the inclined plane writing:-
In the Discourses he developed his ideas of the inclined plane writing:-
I assume that the speed acquired by the same movable object over different inclinations of the plane are equal whenever the heights of those planes are equal.
He also did an experiment with a pendulum about bodies in free fall.
The time in which a certain distance is traversed by an object moving under uniform acceleration from rest is equal to the time in which the same distance would be traversed by the same movable object moving at a uniform speed of one half the maximum and final speed of the previous uniformly accelerated motion.
He then recorded his famous results that the distance that a body moves from rest under uniform acceleration is proportional to the square of the time taken. He used these results to help him build the first pendulum clock, a cloch that can tell the hour and minute, as opposed to previous clocks that could only tell the hour, In 1640. Galileo died in early 1642.
In 1609, Galileo recieved this letter telling about a new Dutch spyglass:
About ten months ago a report reached my ears that a certain Fleming had constructed a spyglass by means of which visible objects, though very distant from the eye of the observer, were distinctly seen as if nearby. Of this truly remarkable effect several experiences were related, to which some persons believed while other denied them. A few days later the report was confirmed by a letter I received from a Frenchman in Paris, Jacques Badovere, which caused me to apply myself wholeheartedly to investigate means by which I might arrive at the invention of a similar instrument. This I did soon afterwards, my basis being the doctrine of refraction.
From these reports, and using his own technical skills, Galileo began to make telescopes that were much better than the Dutch one. His first telescope was able to magnify up to 4 times. His discoveries with his telescope were recorded in a book, Starry Messenger published in 1610. Galileo claimed to have seen mountains on the Moon and discovered the milky way was made up of stars. Galileo fist veiwed Saturn with his telescope on 25 July 1610 and it appeared as three bodies (his telescope was not good enough to show the rings but made them appear as blobs on both sides of the planet). Also in 1610 he discovered that, when seen in the telescope, the planet Venus showed phases like those of the Moon, and therefore must orbit the Sun not the Earth. Galileo became the chief of mathmaticians at the University of Pisa. He became a member of the Accademia dei Lincei. He studied the 4 moons of Jupiter. In his telescope, he looked at Saturn and it looked like it had three bodies on it. He discovered that Venus had phases like the moon does. He observed sunspots and recorded them in the book that he wrote. Galileo then became to study some comets. As you may remember, Gallileo was a supporter of Copernicus, and believed that the earth rotated around the sun. In 1616, he wrote this letter that proysted the followers of Aristotle, who believed the oposite:
I hold that the Sun is located at the centre of the revolutions of the heavenly orbs and does not change place, and that the Earth rotates on itself and moves around it. Moreover ... I confirm this view not only by refuting Ptolemy's and Aristotle's arguments, but also by producing many for the other side, especially some pertaining to physical effects whose causes perhaps cannot be determined in any other way, and other astronomical discoveries; these discoveries clearly confute the Ptolemaic system, and they agree admirably with this other position and confirm it.
The cardinals of the Inquisition met on 24 February 1616 to present evidence and decide if the bible says Copernicus's theory was wrong. Galileo's accusation at the trial which followed was that he had breached the conditions laid down by the Inquisition in 1616. After the trial, Galileo was no longer allowed to study the Copernican theory. Galileo was found guilty and he was condemned to lifelong imprisonment, although it was only house arrest. He was able to live first with the Archbishop of Siena, then later to return to his home in Arcetri, near Florence, but had to spend the rest of his life watched over by officers from the Inquisition. In 1634 he was heartbrocken to find out his daughter, virginia, had died. She had been a great help to her father in his sickness and Galileo was shattered and could not work for many months. When he did get back to work, he wrote Discourses and mathematical demonstrations, concerning the two new sciences. When he finished his work on Discurages, it was smugled out of Italy to London, where it was published. In the Discourses he developed his ideas of the inclined plane writing:-
In the Discourses he developed his ideas of the inclined plane writing:-
I assume that the speed acquired by the same movable object over different inclinations of the plane are equal whenever the heights of those planes are equal.
He also did an experiment with a pendulum about bodies in free fall.
The time in which a certain distance is traversed by an object moving under uniform acceleration from rest is equal to the time in which the same distance would be traversed by the same movable object moving at a uniform speed of one half the maximum and final speed of the previous uniformly accelerated motion.
He then recorded his famous results that the distance that a body moves from rest under uniform acceleration is proportional to the square of the time taken. He used these results to help him build the first pendulum clock, a cloch that can tell the hour and minute, as opposed to previous clocks that could only tell the hour, In 1640. Galileo died in early 1642.
"Galileo biography." MacTutor History of Mathematics. 12 Feb. 2009 <http://www-history.mcs.st-andrews.ac.uk/Biographies/Galileo.html>.
"Galileo biography." MacTutor History of Mathematics.07 Feb. 2009
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